Abstract
Hunter syndrome is an X-linked metabolic storage disorder arising from deficiency of iduronate sulfatase enzyme activity. Despite the successful use of hematopoietic cell transplantation for a variety of lysosomal and peroxisomal storage diseases, limited benefit occurs following transplantation in either the severe or mild forms of Hunter syndrome. A brief ethical commentary is provided on the case of a boy with mucopolysaccharidosis IIB (ie the mild form) who received an unrelated umbilical cord blood transplant to improve his future quality of life. Bone Marrow Transplantation (2000) 25, 1097–1099.